<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    html,
    body {
      height: 100%;
    }

    body {
      display: flex;
      align-items: center;
      justify-content: center;
    }

    iframe {
      opacity: 0;
    }

    .box {
      position: fixed;
      top: 0;
      right: 17px;
      left: 0;
      bottom: 56px;
      z-index: -1;
      display: flex;
      align-items: center;
      justify-content: center;
      flex-direction: column;
    }

    .play {
      font-size: 30px;
    }
  </style>
  <script>
    // window.onbeforeunload = function() {
    //   console.log(123)
    //   return false;
    // };
  </script>
</head>

<body>
  <div>
    <iframe src="http://localhost:3000/"></iframe>
    <div class="box">
      <h1>美女在线聊天</h1>
      <button class="play">点击视频</button>
    </div>
  </div>
</body>

</html>
